With development of network technologies, WLAN (Wireless Local Area Networks) technologies have been widely applied by individuals, families, and enterprises in places such as airports, hotels, and public recreation and entertainment places, and conference and exhibition halls. A WLAN provides a wireless broadband data access service, for example, data service offloading in a cellular network. That is, when arriving in an area within coverage of a WLAN, a user may select the WLAN network to perform a data service. The WLAN also provides some sensor application services, such as smart metering, medical treatment, environment monitoring, and home automation.
A wireless broadband data access service has a relatively high rate and relatively high power consumption, while a sensor application service has a feature of relatively low rate and relatively low power consumption. When an AP (Access Point) supports both the two types of services, that is, STAs (Station) for both the two types of services exist. In the following, a STA for the sensor application service is referred to as a sensor station, and a STA for the wireless broadband data access service is referred to as a non-sensor station. Transmit power of the sensor station is relatively low, and the sensor station is a hidden node relative to the non-sensor station in many cases. When the sensor station sends data, the non-sensor station fails to listen to a channel, and therefore mistakenly considers that the channel is idle and occupies the channel to send data. As a result, a data packet of the sensor station collides with a data packet of the non-sensor station and fails to be sent. After the collision, the data packet of the sensor station is retransmitted for multiple times, thereby increasing power consumption of the sensor station. In addition, the non-sensor station has a large traffic volume and occupies the channel for a long time. Therefore, when the non-sensor station occupies the channel, the sensor station needs to repeatedly listen on the channel, or repeatedly sleep and wake up to listen on the channel, which also increases the power consumption of the sensor station.